U.S. patent number 11,418,004 [Application Number 16/316,109] was granted by the patent office on 2022-08-16 for element structure and light-emitting device.
This patent grant is currently assigned to SONY SEMICONDUCTOR SOLUTIONS CORPORATION. The grantee listed for this patent is SONY SEMICONDUCTOR SOLUTIONS CORPORATION. Invention is credited to Shinichi Agatuma.
United States Patent |
11,418,004 |
Agatuma |
August 16, 2022 |
Element structure and light-emitting device
Abstract
Provided is an element structure includes a heat dissipation
member and a support member provided on the heat dissipation
member. The support member includes a first mount material, a
stress relaxation layer, and a second mount material in a stacking
direction. The element structure further includes a functional
element provided on the support member.
Inventors: |
Agatuma; Shinichi (Miyagi,
JP) |
Applicant: |
Name |
City |
State |
Country |
Type |
SONY SEMICONDUCTOR SOLUTIONS CORPORATION |
Kanagawa |
N/A |
JP |
|
|
Assignee: |
SONY SEMICONDUCTOR SOLUTIONS
CORPORATION (Kanagawa, JP)
|
Family
ID: |
1000006497369 |
Appl.
No.: |
16/316,109 |
Filed: |
May 18, 2017 |
PCT
Filed: |
May 18, 2017 |
PCT No.: |
PCT/JP2017/018671 |
371(c)(1),(2),(4) Date: |
January 08, 2019 |
PCT
Pub. No.: |
WO2018/016164 |
PCT
Pub. Date: |
January 25, 2018 |
Prior Publication Data
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|
|
|
Document
Identifier |
Publication Date |
|
US 20210288465 A1 |
Sep 16, 2021 |
|
Foreign Application Priority Data
|
|
|
|
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Jul 22, 2016 [JP] |
|
|
JP2016-144097 |
|
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
H01S
5/023 (20210101); H01S 5/0216 (20130101); H01S
5/02469 (20130101); H01S 5/0237 (20210101) |
Current International
Class: |
H01S
5/024 (20060101); H01S 5/023 (20210101); H01S
5/02 (20060101); H01S 5/0237 (20210101) |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
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103620764 |
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Mar 2014 |
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CN |
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2721636 |
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Apr 2014 |
|
EP |
|
02-257689 |
|
Oct 1990 |
|
JP |
|
04-286177 |
|
Oct 1992 |
|
JP |
|
11-307875 |
|
Nov 1999 |
|
JP |
|
2001-127375 |
|
May 2001 |
|
JP |
|
2004-200499 |
|
Jul 2004 |
|
JP |
|
2004-349294 |
|
Dec 2004 |
|
JP |
|
2004-356429 |
|
Dec 2004 |
|
JP |
|
2006-100369 |
|
Apr 2006 |
|
JP |
|
2006-294943 |
|
Oct 2006 |
|
JP |
|
2006-344743 |
|
Dec 2006 |
|
JP |
|
2008-172141 |
|
Jul 2008 |
|
JP |
|
2008-311556 |
|
Dec 2008 |
|
JP |
|
2009-043806 |
|
Feb 2009 |
|
JP |
|
2009-111065 |
|
May 2009 |
|
JP |
|
2014-518450 |
|
Jul 2014 |
|
JP |
|
2014-225660 |
|
Dec 2014 |
|
JP |
|
10-2014-0098109 |
|
Aug 2014 |
|
KR |
|
2012/173631 |
|
Dec 2012 |
|
WO |
|
Other References
International Search Report and Written Opinion of PCT Application
No. PCT/JP2017/018671, dated Aug. 1, 2017, 11 pages of ISRWO. cited
by applicant .
Office Action for JP Patent Application No. 2018-528416, dated Mar.
9, 2021, 03 pages of English Translation and 02 pages of Office
Action. cited by applicant .
Office Action for Japanese Application No. 2018-528416 dated Jan.
5, 2021. cited by applicant.
|
Primary Examiner: Zhang; Yuanda
Attorney, Agent or Firm: Chip Law Group
Claims
The invention claimed is:
1. An element structure, comprising: a heat dissipation member; a
support member on the heat dissipation member, wherein the support
member includes: a first mount material, a stress relaxation layer,
and a second mount material in order from a side of the heat
dissipation member, wherein each of the first mount material and
the second mount material includes an electrically conductive
material, and the stress relaxation layer is in a region excluding
a peripheral part of the support member such that a length of the
stress relaxation layer is smaller than a length of each of the
first mount material and the second mount material; and a thermally
conductive insulating layer between the second mount material and
the stress relaxation layer; and a functional element on the
support member, wherein the second mount material is between the
functional element and the stress relaxation layer.
2. The element structure according to claim 1, wherein the
electrically conductive material includes at least one of silicon
carbide (SiC), copper, aluminum, a copper-tungsten alloy (Cu--W),
or a copper-molybdenum alloy (Cu--Mo).
3. The element structure according to claim 1, wherein the
thermally conductive insulating layer includes aluminum
nitride.
4. The element structure according to claim 1, wherein the stress
relaxation layer includes at least one of tin (Sn), indium (In), or
aluminum (Al).
5. The element structure according to claim 1, wherein the stress
relaxation layer includes a multi-layer film.
6. The element structure according to claim 1, wherein the
functional element comprises a light-emitting element.
7. The element structure according to claim 6, wherein the
light-emitting element comprises a semiconductor laser.
8. A light-emitting device, comprising: a heat dissipation member;
a support member on the heat dissipation member, wherein the
support member includes: a first mount material, a stress
relaxation layer, and a second mount material in order from a side
of the heat dissipation member, wherein each of the first mount
material and the second mount material includes an electrically
conductive material, and the stress relaxation layer is in a region
excluding a peripheral part of the support member such that a
length of the stress relaxation layer is smaller than a length of
each of the first mount material and the second mount material; and
a thermally conductive insulating layer between the second mount
material and the stress relaxation layer; and a light-emitting
element on the support member, wherein the second mount material is
between the light-emitting element and the stress relaxation layer.
Description
CROSS REFERENCE TO RELATED APPLICATIONS
This application is a U.S. National Phase of International Patent
Application No. PCT/JP2017/018671 filed on May 18, 2017, which
claims priority benefit of Japanese Patent Application No. JP
2016-144097 filed in the Japan Patent Office on Jul. 22, 2016. Each
of the above-referenced applications is hereby incorporated herein
by reference in its entirety.
TECHNICAL FIELD
The present disclosure relates to an element structure and a
light-emitting device including the element structure.
BACKGROUND ART
In recent years, a light-emitting element such as a semiconductor
laser has been used as a light source for various types of
electronic apparatuses such as a high-density optical disk
apparatus, a laser beam printer, and a full-color display.
Such a light-emitting element is mounted on a heat dissipation
member such as a heat sink via a support member such as a sub-mount
(PTLs 1 to 6, for example).
CITATION LIST
Patent Literature
PTL 1: Japanese Unexamined Patent Application Publication No.
2006-100369
PTL 2: Japanese Unexamined Patent Application Publication No.
2009-43806
PTL 3: Japanese Unexamined Patent Application Publication No.
H4-286177
PTL 4: Japanese Unexamined Patent Application Publication No.
2006-344743
PTL 5: Japanese Unexamined Patent Application Publication No.
2004-200499
PTL 6: Japanese Unexamined Patent Application Publication No.
2014-225660
SUMMARY OF THE INVENTION
In an element structure including a light-emitting element as
described above, stress is easily generated due to a difference in
thermal expansion coefficients between members. It is desirable to
provide an element structure and a light-emitting device which make
it possible to reduce influence of stress on a functional element
such as a light-emitting element.
An element structure according to an embodiment of the present
disclosure includes a heat dissipation member, a support member
provided on the heat dissipation member and including therein a
stress relaxation layer in a stacking direction, and a functional
element provided on the support member.
A light-emitting device according to an embodiment of the present
disclosure includes a heat dissipation member, a support member
provided on the heat dissipation member and including therein a
stress relaxation layer in a stacking direction, and a
light-emitting element provided on the support member.
In the element structure and the light-emitting device according to
the respective embodiments of the present disclosure, the support
member provided on the heat dissipation member includes therein the
stress relaxation layer in the stacking direction. The stress
relaxation layer absorbs or divides the stress generated due to the
difference in the thermal expansion coefficients between the heat
dissipation member and the support member, for example.
In the element structure and the light-emitting device according to
the respective embodiments of the present disclosure, the support
member provided on the heat dissipation member includes therein the
stress relaxation layer in the stacking direction. This enables the
stress generated due to the difference in the thermal expansion
coefficients between the heat dissipation member and the support
member, for example, to be absorbed or divided, thus making it
possible to inhibit the stress from being applied to the functional
element (light-emitting element) on the support member. It becomes
possible to reduce the influence of the stress on the functional
element.
It is to be noted that the effects of the disclosure are not
limited to those described above, and may be any of the effects
described herein.
BRIEF DESCRIPTION OF DRAWINGS
FIG. 1 is a perspective view of a configuration example of a
light-emitting device according to a first embodiment of the
present disclosure.
FIG. 2 is an enlarged view of a configuration of an element
structure illustrated in FIG. 1.
FIG. 3 is a schematic cross-sectional view of a configuration
example of a support member illustrated in FIG. 2.
FIG. 4A is an explanatory schematic cross-sectional view of a
manufacturing process of the support member illustrated in FIG.
2.
FIG. 4B is a schematic cross-sectional view of a process following
FIG. 4A.
FIG. 4C is a schematic cross-sectional view of a process following
FIG. 4B.
FIG. 5 is a schematic cross-sectional view of a configuration
example of a support member of a light-emitting device according to
a second embodiment of the present disclosure.
FIG. 6 is a schematic cross-sectional view of a configuration
example of a support member according to Modification Example
1.
FIG. 7 is a schematic cross-sectional view of a configuration
example of a support member according to Modification Example
2.
FIG. 8 is a schematic cross-sectional view of a configuration
example of a support member according to Modification Example
3.
FIG. 9 is a schematic cross-sectional view of a configuration
example of a support member according to Modification Example
4.
FIG. 10 is a schematic cross-sectional view of a configuration
example of a support member according to Modification Example
5.
FIG. 11 is a schematic cross-sectional view of a configuration
example of a support member according to Modification Example
6.
MODES FOR CARRYING OUT THE INVENTION
In the following, some embodiments of the present disclosure are
described in detail with reference to the drawings. The embodiments
described below each illustrate a specific example of the present
disclosure, and the present disclosure is not limited to the
following embodiments. Moreover, the present disclosure is not
limited to positions, dimensions, dimension ratios, and other
factors of respective components illustrated in the drawings. It is
to be noted that description is given in the following order. 1.
First Embodiment (An example of a light-emitting device having a
stress relaxation layer within a support member of an element
structure) 2. Second Embodiment (An example a case where a mount
material of the support member is electrically conductive) 3.
Modification Example 1 (An example where an insulating layer is
provided between the mount material and the stress relaxation
layer) 4. Modification Example 2 (An example of a case where the
insulating layer is a multi-layer film) 5. Modification Example 3
(An example where the stress relaxation layer is formed in a
selective region of the support member) 6. Modification Example 4
(An example of a case where the stress relaxation layer is a
multi-layer film) 7. Modification Example 5 (An example of a case
where an adhesion layer lies between the stress relaxation layers)
8. Modification Example 6 (An example of a case where a plurality
of mount materials are provided on one side of the stress
relaxation layer)
First Embodiment
[Configuration]
FIG. 1 illustrates a configuration example of a light-emitting
device 1 including an element structure 2 according to a first
embodiment of the present disclosure. FIG. 2 illustrates the
element structure of FIG. 1 in an enlarged manner. The
light-emitting device 1 is used as a light source module for
various types of electronic apparatuses. Examples of the electronic
apparatuses include a high-density optical disk apparatus, a laser
beam printer, and a full-color display.
The light-emitting device 1 includes, for example, the element
structure 2, a stem 30 that serves as a support for the element
structure 2, a lead pin 31 as a coupling terminal, and a bonding
wire 32 electrically coupling the lead pin 31 and the element
structure 2 to each other. The element structure 2 is sealed, as
needed, by an external member having a dome shape or a cylindrical
shape, etc., for example.
The element structure 2 includes a light-emitting element 10, a
support member 11, and a heat dissipation member 12, for example.
The support member 11 and the light-emitting element 10 are
provided in this order on the heat dissipation member 12.
The light-emitting element 10 is, for example, a semiconductor
light-emitting element such as a semiconductor laser. The
light-emitting element 10 is mounted, for example, as a radar diode
chip or a radar diode bar, on the support member 11. However, the
light-emitting element 10 is not limited to the semiconductor
laser, and may be, for example, another semiconductor
light-emitting element such as a light-emitting diode (LED: Light
Emitting Diode) or a super luminescent diode (SLD: Super
luminescent diode). In addition, the light-emitting element 10 is
not limited to such a semiconductor light-emitting element, and may
be an organic electroluminescent element, etc., for example. The
light-emitting element 10 is adhered to the support member 11 by a
solder including an alloy of gold (Au) and tin (Sn), i.e., an
Au--Sn alloy, for example, or by brazing.
The support member 11 includes, for example, the mount material
such as a sub-mount, and supports the light-emitting element 10.
FIG. 3 illustrates a configuration example of the support member
11. The support member 11 includes therein a stress relaxation
layer 11B in a stacking direction. Specifically, the support member
11 has a configuration in which the stress relaxation layer 11B is
interposed between a mount material 11A1 and a mount material 11A2,
for example. It is to be noted that a surface S1 is set as a
surface facing the light-emitting element 10, and a surface S2 is
set as a surface facing the heat dissipation member 12.
It is desirable that the mount materials 11A1 and 11A2 include a
material having high thermal conductivity, for example. Examples of
such a material include a material including diamond, ceramics, and
a material including metal. As constituent materials of the mount
materials 11A1 and 11A2, an appropriate material may be selected in
consideration of thermal expansion coefficients of the
light-emitting element 10 and the heat dissipation member 12. In
the present embodiment, the mount materials 11A1 and 11A2 include a
material having insulation properties (such as the diamond or the
ceramics). Examples of the material include aluminum nitride (AlN)
(having a thermal expansion coefficient of 4.5.times.10.sup.-6
[1/K]) and beryllium oxide (BeO) (having a thermal expansion
coefficient of 7.6.times.10.sup.-6 [1/K]). The total of thicknesses
of the mount materials 11A1 and 11A2 is 200 .mu.m, for example. The
constituent materials of the mount materials 11A1 and 11A2 may be
the same as or different from each other. In addition, the
thicknesses of the mount materials 11A1 and 11A2 may be the same as
or different from each other.
The stress relaxation layer 11B has a capability of absorbing or
dividing stress generated in the element structure 2. Specifically,
the stress relaxation layer 11B absorbs or divides stress due to a
difference in respective thermal expansion coefficients of the
light-emitting element 10, the support member 11, and the heat
dissipation element 12. In addition, the stress relaxation layer
11B absorbs or divides stress due to a difference in thermal
expansion coefficients of the mount materials 11A1 and 11A2. For
example, soft metal may be used for such a stress relaxation layer
11B. Examples of the soft metal include tin (Sn), indium (In), and
aluminum (Al). The stress relaxation layer 11B includes one or more
of these tin, indium, and aluminum. The stress relaxation layer 11B
has a thickness in a range from 1 .mu.m to 100 .mu.m, for example.
As an example, the stress relaxation layer 11B has a thickness in a
range from 10 .mu.m to 20 .mu.m. It is to be noted that an adhesion
layer may lie between the stress relaxation layer 11B and each of
the mount materials 11A1 and 11A2. In this case, it is desirable
that a thermally conductive material be used for the adhesion
layer.
(Method of Manufacturing Support Member 11)
FIGS. 4A, 4B, and 4C illustrate an example of a manufacturing
process of the support member 11. For example, the support member
11 as described above may be manufactured in the following manner.
That is, as illustrated in FIG. 4A, the stress relaxation layer
11B1 including the foregoing soft metal is first formed as a film
on a surface of the mount material 11A1 by means of, for example, a
vapor deposition method, a sputtering method, a plating method, an
ion plating method, or the like. Alternatively, in a case where
eutectic metal is used for the stress relaxation layer 11B1,
eutectic bonding with use of the eutectic metal enables joining
between the mount material 11A1 and the stress relaxation layer
11B1. In addition, the mount material 11A1 and the stress
relaxation layer 11B1 may be joined together with the thermally
conductive adhesion layer being interposed therebetween.
Likewise, the stress relaxation layer 11B2 is also formed as a film
on a surface of another mount material, i.e., the mount material
11A2 by means of a technique similar to the foregoing stress
relaxation layer 11B1, for example. It is to be noted that, in this
example, a case is assumed where the stress relaxation layers 11B1
and 11B2 are configured by the same material. In addition, although
a case is described where the stress relaxation layers 11B1 and
11B2 are respectively formed on the mount materials 11A1 and 11A2,
the stress relaxation layer 11B1 (or the stress relaxation layer
11B2) may be formed only on either the mount material 11A1 or
11A2.
Subsequently, as illustrated in FIG. 4B, the mount materials 11A1
and the mount material 11A2 are joined together to cause the stress
relaxation layers 11B1 and 11B2 to face each other. As a joining
technique, for example, techniques such as thermal compression
bonding, diffusion bonding, anodic bonding, and the eutectic
bonding may be used, similarly to the joining between the mount
material 11A1 and the stress relaxation layer 11B1 as described
above.
This causes the stress relaxation layers 11B1 and 11B2 to be
integrated between the mount material 11A1 and the mount material
11A2, thus forming the stress relaxation layer 11B, as illustrated
in FIG. 4C. Thereafter, peripheral parts of the mount materials
11A1 and 11A2 are processed by means of, for example, dicing, etc.
to each have a desired size. In this manner, the support member 11
including therein the stress relaxation layer 11B in the stacking
direction is completed.
The support member 11 is adhered to the heat dissipation member 12
by the solder including the alloy of gold (Au) and tin (Sn), i.e.,
the Au--Sn alloy, for example, or by the brazing.
The heat dissipation member 12 is configured by a heat sink, for
example, and has a capability of releasing heat generated from the
light-emitting element 10. The heat dissipation member 12 includes,
for example, copper (Cu) having high thermal conductivity.
[Workings and Effects]
The light-emitting device 1 of the present embodiment generates
heat in accordance with power consumption thereof, while the
light-emitting element 10 emits a light (outputs laser light, for
example). In addition, in the manufacturing process of the
light-emitting device 1, the light-emitting element 10, the support
member 11, and the heat dissipation member 12 are adhered by solder
bonding, etc., and thus, for example, heat of 200.degree. C. or
higher is applied to the light-emitting element 10. Although the
heat generated in the light-emitting element 10 is released by the
heat dissipation member 12, the stress due to the difference in the
thermal expansion coefficients of the support member 11 and the
heat dissipation member 12 is generated in the element structure 2
under the influenced of the heat.
Here, for example, a technique as described in the following is
proposed to reduce the foregoing stress. That is, in the element
structure as described in PTLs 1 and 2, for example, an electrode
layer having a partially large thickness is provided between the
mount material and the light-emitting element, and an attempt to
reduce the stress is made using the electrode layer. In the element
structure utilizing the electrode layer, however, in a case where
the stress from the heat dissipation member such as the heat sink
is large, the large stress is applied to the light-emitting element
via the mount material. In addition, in the element structure
described in the foregoing PTLs 3 and 4, for example, use of a
two-layered mount material allows for reduction of the stress due
to the difference in the thermal expansion coefficients between the
light-emitting element and an upper mount material. In the element
structure using the two-layered mount material, however, the stress
due to the difference in the thermal expansion coefficients between
a lower mount material and the heat dissipation member influences
the light-emitting element; or the stress due to the difference in
the thermal expansion coefficients between the upper mount material
and the lower mount material influences the light-emitting
element.
In contrast, in the present embodiment, the support member 11
provided on the heat dissipation member 12 includes therein the
stress relaxation layer 11B in the stacking direction.
Specifically, the support member 11 includes the stress relaxation
layer 11B between a pair of the mount materials 11A1 and 11A2. The
stress relaxation layer 11B absorbs or divides the stress generated
due to the difference in the thermal expansion coefficients between
the heat dissipation member 12 and the support member 11, for
example, thus inhibiting the stress from being applied to the
light-emitting element 10 on the support member 11.
In addition, in the present embodiment, it is also possible to
absorb or divide the stress generated due to the difference in the
thermal expansion coefficients between the two mount materials 11A1
and 11A2 in the support member 11. It is possible to inhibit the
stress generated between such mount materials 11A1 and 11A2 from
being applied to the light-emitting element 10.
Furthermore, in the present embodiment, the mount materials 11A1
and 11A2 include an insulating material (AlN, for example), thus
making it possible to inhibit generation of a leak current in the
support member 11.
As described above, in the present embodiment, the support member
11 provided on the heat dissipation member 12 includes therein the
stress relaxation layer 11B in the stacking direction. This enables
the stress generated due to the difference in the thermal expansion
coefficients between the heat dissipation member 12 and the support
member 11, for example, to be absorbed or divided, thus making it
possible to inhibit the stress from being applied to the
light-emitting element 10 on the support member 11. It becomes
possible to reduce the influence of the stress on the
light-emitting element 10.
Next, description is given of another embodiment and modification
examples of the present disclosure. In the following, same
components as those of the foregoing first embodiment are denoted
by same reference numerals, and description thereof is omitted
where appropriate.
Second Embodiment
FIG. 5 illustrates a configuration example of the support member 11
of the element structure 2 according to a second embodiment of the
present disclosure. Similarly to the foregoing first embodiment,
the support member 11 of the present embodiment is also provided
between the light-emitting element 10 and the heat dissipation
member 12 to configure the element structure 2.
Similarly to the foregoing first embodiment, the support member 11
of the present embodiment includes therein the stress relaxation
layer 11B in the stacking direction. Specifically, the support
member 11 of the present embodiment has a configuration in which
the stress relaxation layer 11B is interposed between a mount
material 11C1 and a mount material 11C2. In the present embodiment,
however, the mount materials 11C1 and 11C2 include an electrically
conductive material (such as a conductor or a semiconductor),
unlike the mount materials 11A1 and 11A2 of the foregoing first
embodiment.
It is desirable that the mount materials 11C1 and 11C2 include a
material being electrically conductive and highly thermally
conductive. Examples of the material include silicon carbide (SiC)
(having a thermal expansion coefficient of 3.8.times.10.sup.-6
[1/K]), for example. Other examples of the material include copper,
aluminum, a copper-tungsten alloy (Cu--W) and a copper-molybdenum
alloy (Cu--Mo). The total of thicknesses of the mount material 11C1
and the mount material 11C2 is 200 .mu.m, for example. The
constituent materials of the mount materials 11C1 and 11C2 may be
same as or different from each other. The thicknesses of the mount
material 11C1 and the mount material 11C2 may be same as or
different from each other.
It is also possible to manufacture the support member 11 by forming
the stress relaxation layers 11B1 and 11B2 on respective surfaces
of the mount materials 11C1 and 11C2 and thereafter joining them
together.
Also in the present embodiment, the support member 11 includes
therein the stress relaxation layer 11B in the stacking direction,
and thus the stress generated due to the difference in the thermal
expansion coefficients between the heat dissipation member 12 and
the support member 11, for example, is absorbed or divided. This
makes it possible to inhibit the stress from being applied to the
light-emitting element 10 on the support member 11. Hence, it is
possible to achieve the effects substantially equivalent to those
of the foregoing first embodiment.
MODIFICATION EXAMPLE 1
FIG. 6 illustrates a configuration example of a support member
according to a modification example (Modification Example 1) of the
foregoing second embodiment. In the support member of the present
modification example, an insulating layer 11D is provided between
each of the mount materials 11C1 and 11C2 and the stress relaxation
layer 11B in a stacked structure of the foregoing second
embodiment.
The insulating layer 11D includes an insulating material having
high thermal conductivity, for example. Such an insulating layer
11D includes, for example, one or more of aluminum nitride, boron
nitride (BN), silicon oxide (SiO.sub.2), silicon nitride
(Si.sub.3N.sub.4), aluminum oxide (Al.sub.2O.sub.3), zirconium
oxide (ZrO), aluminum oxynitride (AlO.sub.xN.sub.x-1), zinc oxide
(ZnO), and tantalum oxide (Ta.sub.2O.sub.5), etc.
In this manner, the insulating layer 11D may lie between each of
the mount materials 11C1 and 11C2 and the stress relaxation layer
11B. In this case, it is also possible to achieve the effects
equivalent to those of the foregoing first embodiment. In addition,
in a case where the electrically conductive mount materials 11C1
and 11C2 are used for the support member, the leak current may be
generated. However, it is possible to inhibit generation of such a
leak current because of the insulating layer 11D lying
therebetween. It is to be noted that, in the present modification
example, the insulating layer 11D is formed between each of the
mount materials 11C1 and 11C2 and the stress relaxation layer 11B;
however, the insulating layer 11D may be formed only between one of
the mount materials 11C1 and 11C2 and the stress relaxation layer
11B. Moreover, the stress relaxation layer 11B either may be formed
on both sides of the mount materials 11C1 and 11C2, or may be
formed only on one of the mount materials 11C1 and 11C2.
MODIFICATION EXAMPLE 2
FIG. 7 illustrates a configuration example of a support member
according to a modification example (Modification Example 2) of the
foregoing second embodiment. In the foregoing Modification Example
1, description has been given of the configuration in which the
insulating layer 11D is provided between each of the mount
materials 11C1 and 11C2 and the stress relaxation layer 11B.
However, the insulating layer 11D may be a multi-layer film
including a plurality of layers as in the present modification
example. Specifically, the insulating layer 11D may be a
multi-layer film including two insulating layers 11D1 and 11D2, for
example. As the constituent materials of the insulating layers 11D1
and 11D2, insulating materials similar to those listed as the
material for the foregoing insulating layer 11D may be used. The
constituent materials of the insulating layers 11D1 and 11D2 may be
same as or different from each other. In addition, the thicknesses
of the insulating layers 11D1 and 11D2 may be same as or different
from each other.
It is to be noted that the insulating layer 11D is not limited to
the configuration described above, and may be a multi-layer film of
three or more layers. In addition, the insulating material may be
same or different between the insulating layer 11D on side of the
mount material 11C1 and the insulating layer 11D on side of the
mount material 11C2. Moreover, the number of the layers and the
thickness may be same or different between the insulating layer 11D
on the side of the mount material 11C1 and the insulating layer 11D
on the side of the mount material 11C2.
MODIFICATION EXAMPLE 3
FIG. 8 illustrates a configuration example of a support member
according to Modification Example 3. In the support member of the
present modification example, the stress relaxation layer 11B is
formed in a selective region of the support member. For example,
the stress relaxation layer 11B is formed in a region excluding a
peripheral region D of the support member (mount materials 11A1 and
11A2).
Although the stress relaxation layer 11B may be formed throughout
the mount materials 11A1 and 11A2, the stress relaxation layer 11B
may be formed only in a selective region as in the present
modification example. For example, the stress relaxation layer 11B
formed in the region excluding the peripheral region D makes it
easier to perform processing such as dicing in the manufacturing
process of the foregoing support member, for example.
MODIFICATION EXAMPLE 4
FIG. 9 illustrates a configuration example of a support member
according to Modification Example 4. In the foregoing first
embodiment, etc., description has been given of the configuration
in which the stress relaxation layer 11B is provided between the
mount materials 11A1 and 11A2. However, the stress relaxation layer
11B may include a multi-layer film configured by a plurality of
layers, as in the present modification example. Specifically, the
stress relaxation layer 11B may be a multi-layer film including two
stress relaxation layers 11B3 and 11B4, for example. Soft metal
similar to those listed as the material for the foregoing stress
relaxation layer 11B may be used for the stress relaxation layers
11B3 and 11B4. The constituent materials of the stress relaxation
layers 11B3 and 11B4 may be same as or different from each other.
In addition, the thicknesses of the stress relaxation layers 11B3
and 11B4 may be same as or different from each other.
It is to be noted that the stress relaxation layer 11B is not
limited to the configuration described above, and may be a
multi-layer film of three or more layers.
MODIFICATION EXAMPLE 5
FIG. 10 illustrates a configuration example of a support member
according to Modification Example 5. In the foregoing Modification
Example 4, description has been given of the case where the stress
relaxation layer 11B is the multi-layer film including the two
stress relaxation layers 11B3 and 11B4. However, in the present
modification example, an adhesion layer 11E lies between the stress
relaxation layers 11B3 and 11B4. It is desirable that the adhesion
layer 11E be configured by a material having high thermal
conductivity. In this manner, another layer (adhesion layer 11E,
for example) may lie between the stress relaxation layers 11B3 and
11B4.
MODIFICATION EXAMPLE 6
FIG. 11 illustrates a configuration example of a support member
according to Modification Example 6. In the foregoing first
embodiment, etc., the configuration is exemplified in which the
stress relaxation layer 11B is provided between the two mount
materials 11A1 and 11A2 (or the two mount materials 11C1 and 11C2).
However, the mount material provided in the support member may be
three or more (three layers or more). As an example, FIG. 11
illustrates a configuration in which the mount materials 11A1 and
11A2 including an insulating material and the electrically
conductive mount materials 11C1 and 11C2 are stacked.
In this manner, a plurality of mount materials may be joined
together to interpose the stress relaxation layer 11B. Moreover,
the constituent material, the number, and the thickness, etc. of
the mount material provided between the stress relaxation layer 11B
and the surface S1, and the constituent material, the number, and
the thickness, etc. of the mount material provided between the
stress relaxation layer 11B and the surface S2 may be same as or
different from each other.
Although the description has been given with reference to the
embodiments and the modification examples, the present disclosure
is not limited to the foregoing embodiments, etc., and may be
modified in a variety of ways. For example, the materials, the
thicknesses, and the film-forming methods, etc., of the respective
layers described in the foregoing embodiments are not limitative,
and any other material, any other thickness, and any other
film-forming method may be adopted.
In addition, although the foregoing embodiments, etc. exemplify the
configuration in which the element structure 2 includes the
light-emitting element 10, the element structure 2 may include any
element (functional element) other than the light-emitting element.
Examples of the functional element may include a diode, a
small-signal transistor, a power transistor, a rectifier element, a
thyristor, and an optical element.
Moreover, the present disclosure may have the following
configurations, for example.
(1)
An element structure including:
a heat dissipation member;
a support member provided on the heat dissipation member and
including therein a stress relaxation layer in a stacking
direction; and
a functional element provided on the support member.
(2)
The element structure according to (1), in which the support member
includes a first mount material, the stress relaxation layer, and a
second mount material in order from side of the heat dissipation
member.
(3)
The element structure according to (2), in which the first and
second mount materials each include an insulating material.
(4)
The element structure according to (3), in which the insulating
material is aluminum nitride (AlN).
(5)
The element structure according to any one of (2) to (4), in which
the first and second mount materials each include an electrically
conductive material.
(6)
The element structure according to (5), in which the support member
includes a thermally conductive insulating layer between each of
the first and second mount materials and the stress relaxation
layer.
(7)
The element structure according to (5) or (6), in which the
electrically conductive material is silicon carbide (SiC).
(8)
The element structure according to (6), in which the insulating
layer includes one or more of aluminum nitride, boron nitride (BN),
silicon oxide (SiO.sub.2), silicon nitride (Si.sub.3N.sub.4),
aluminum oxide (Al.sub.2O.sub.3), zirconium oxide (ZrO), aluminum
oxynitride (AlO.sub.xN.sub.x-1), zinc oxide (ZnO), and tantalum
oxide (Ta.sub.2O.sub.5).
(9)
The element structure according to any one of (1) to (8), in which
the stress relaxation layer is formed in a region excluding a
peripheral part of the support member.
(10)
The element structure according to any one of (1) to (9), in which
the stress relaxation layer includes one or more of tin (Sn),
indium (In), and aluminum (Al).
(11)
The element structure according to any one of (1) to (10), in which
the stress relaxation layer includes a multi-layer film.
(12)
The element structure according to any one of (1) to (11), in which
the functional element is a light-emitting element.
(13)
The element structure according to (12), in which the
light-emitting element is a semiconductor laser.
(14)
A light-emitting device including:
a heat dissipation member;
a support member provided on the heat dissipation member and
including therein a stress relaxation layer in a stacking
direction; and
a light-emitting element provided on the support member.
This application claims the benefit of Japanese Priority Patent
Application No. 2016-144097 filed with the Japan Patent Office on
Jul. 22, 2016, the entire contents of which are incorporated herein
by reference.
It should be understood by those skilled in the art that various
modifications, combinations, sub-combinations, and alterations may
occur depending on design requirements and other factors insofar as
they are within the scope of the appended claims or the equivalents
thereof.
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